This report aims at comparing the Behind Armour Debris (BAD) generated by the penetration of a shaped charge jet into two common vehicle armour materials: 5083 aluminium alloy and Rolled Homogeneous Armour (RHA) steel. A statically detonated 66 mm shaped charge was used for the tests, which took place at the DRDC Valcartier exterior ranges. Targets were tested for thicknesses between 1.6 mm and 127.5 mm for RHA and 13 mm to 133 mm for 5083 aluminium alloy. Witness packs were used to record the behind armour debris, then scanned and analysed to obtain the behind armour debris distributions (fragment position, mass, velocity and lethality). Comparing number of fragments versus thickness, aluminium has shown to produce about 60% less fragments around 13 mm. This difference gradually goes down to twice less for the thickest targets. Number of BAD in RHA reaches a peak around 12 mm (94 kg/m2) then decreases with thickness. For aluminium, targets thinner than 13 mm (35 kg/m2) were not tested, therefore the exact location of the peak in BAD is not visible in the test results, but from 13 mm to 127.5 mm, a gradual decrease in BAD was found. The fragment mass and velocity distributions are similar for both materials, but since aluminium produces fewer fragments, the lethality of the debris cone is smaller for aluminium. Predictive equations to numerically reproduce the behind armour debris distributions were developed based on the test results and are presented.